1. Field of the Invention
This invention relates in general to a structure of a novel laser scanning apparatus. More specifically, this invention relates to a laser scanning apparatus apparatus which also has an additional optical signal sending or receiving capability, not only an optical output function to visualize a picture as a display.
2. Description of the Prior Art
Conventionally, a CRT (Cathode Ray Tube) display and an LCD (Liquid Crystal Display) have been the most well known and popular display system for picture or video display. Both display systems are widely used for home-entertaining or computing systems.
However, as for the CRT display, the most serious disadvantage must be its thickness. Because of the limitation to deflect an electron beam emitted from an electron gun, it requires longer distance between a screen to the electron gun in order to display larger picture. Eventually, it sets a limit of the size of the display. In addition, to produce even more precise picture with high resolution, high definition TV system which has four times as much number of pixels as ordinal CRT television system has been proposed. However, this system also has a limit to scan the electron beam to vast number of pixels.
As for the LCD system, structural disadvantage sets a limit of the number of the pixels, which are controlled by transistors individually. That is why very large liquid crystal display has never provided yet. In addition, malfunctioning of the transistor could seriously reduce the manufacturing yield.
Various display systems are known which incorporate the capability for writing and pointing onto the CRT or LCD, along with a detector for sensing and encoding the location of the pen or finger of the operator. For example, touch-screen system cooperated with the addresser, central signal processing unit or interface is currently used for signal input and output device with television or computer. However, this prior-art system is capable to only recognize the location of the pen or finger, and unable to transmit complicated command or send signals by way of a central signal processing unit or an interface to linked optical fiber communication network.
Accordingly, it is desirable to provide a novel interactive display system which reduces thickness and weight, and produces high precision picture. Additionally, an interactive optical display system must be needed to accomplish broad interactive optical fiber communication network which may provide a lot of new services such as video-on-demand. The present invention will be able to provide an interactive flat all-optical display system which has great advantages and many applications for the advanced optical fiber communication network system in near coming future.